Yavin IV: Exploring space on the cheap with an iPhone, Droid, and Flip

A group of "self-admitted nerds" collaborate to send a weather balloon into …

Many a nerd has dreamed of exploring space—the final frontier—as a child. Despite visions in books, comics, TV, and film of a future where space travel is commonplace, that dream is still far from reality. But a handful of "self-admitted nerds" from the interactive design firm Sevnthsin are taking to the skies with a weather balloon, a hacked cooler, and the latest in mobile technology.

Calling their project Yavin IV (after a rebel base in the Star Wars universe), the small group from Minneapolis, Minnesota completed their first full launch on Friday. Ars was on the scene to capture the event, and we spoke with project leader Jamey Erickson to understand what the project is trying to accomplish, and what's in store for its future.

The project first started after some interoffice goading from Sevnthsin senior developer Jessie Ross. Erickson and Ross are long-time friends, and have a pact to go on a Virgin Galactic space orbit trip the minute the service is available to the general public.

Jamey Erickson prepping the balloon, helium tank, and "capsule" for last Friday's launch.

"It stems from being an open office of self-admitted nerds," Erickson told Ars. Sevnthsin is an interactive design firm focused on mobile and social networking technologies, so the idea was hatched to leverage the advances in mobile technology to explore space. Taking a cue from a similar experiment performed recently at MIT, the pair decided to send up a weather balloon to the threshold of "space," with an iPhone shooting still images, a Flip camera shooting video, and a Droid Eris for GPS tracking.

"We realized that launching a balloon would be something doable," Erickson said. "We also wanted to test the limits of mobile technology. Why couldn't we do all this with cellphones?" Erickson said the fledgeling project decided to see what was possible using off-the-shelf mobile devices paired with available apps.

The Yavin VI "capsule" is made from a small Igloo cooler, with viewports cut out and covered with plexiglass. You can see the SharkFinTail™ added for stability.

The iPhone used a time-lapse app to take photos on a regular schedule. The team chose a Droid Eris running Loopt to track the landing, since Verizon's network covers nearly all of Wisconsin where the balloon was expected to land. A Flip was turned on and set to record just before the payload was bundled up and the balloon launched.

Instead of hauling sixers for tailgating, this cooler is packed with an iPhone, a Droid Eris, a Garmin GPS unit, and a Flip video camera, along with hand warmers to keep everything from freezing in the upper atmosphere.

The group did a test launch on September 17—a "dress rehearsal," according Erickson, that ran into a few technical glitches which limited maximum altitude. "We discovered some things we didn't account for, some errors in our process, but it went as well as we could have expected," he told Ars.

I've assisted a group with something similar. We used APRS for tracking..things got interesting when the unit crossed over into the neighbouring countries airspace.Still it's very cool how these guys used off the shelve gear for communications, photo and video. Nice work

Obviously there are limits to helium... How much would it take to launch a small payload to orbit with rockets? Obviously the cost would be much higher, but I'm still curious... or if it'd even be remotely legal

What happens to the payload after the balloon pop? Does it just drop? Or is there a parachute? While unlikely, getting hit by a playmate cooler that has dropped 100,000 feet is likely to hurt.... the equipment inside.

Quick googling shows that using civilian GPS units for altitude is a no-no. Both by law and technological limitations. A barometric pressure sensor would be the way to go. Some of the smartphones with 6-axis sensor packages could also be used as a poor man's AHRS to approximate altitude better than was done here.

Civilian GPS units over a certain altitude (20,000 AGL?) either have to disable their location reporting, or disable their altitude reporting. The fear causing this limitation is that nefarious people could use such devices for missile guidance or some such nonsense. Also, most people doing these types of projects don't use cell phones, as the phone companies really don't like it when a phone can ping 500 towers at once, so they usually use Ham radio, with a packet radio system running to send back telemetry. I would be curious to see if someone could do this with unlicensed 802.11.

It's pretty cool that they're doing a lot of the same things as the folks at Edge of Space Science (http://www.eoss.org/) with consumer electronics. EOSS uses custom-engineered embedded hardware to build an extremely lightweight platform with lots of neat telemetry capabilities, but these guys show you don't need all that for a simple high-elevation balloon flight..

Just got off the phone with Jamey Erickson to get some answers to your questions.

mto wrote:

Anyone know what the gold reflector was for?

It's a radar reflector required by FAA regulations, so that air traffic control can track it.

end wrote:

What happens to the payload after the balloon pop? Does it just drop? Or is there a parachute? While unlikely, getting hit by a playmate cooler that has dropped 100,000 feet is likely to hurt.... the equipment inside.

There is a chute that is deployed when the balloon breaks.

_NARC_ wrote:

What is the recovery mechanism? I'm assuming that they have a parachute, but was it altitude-deployed or dragging the whole time?

Jamey said that it doesn't open up until the balloon breaks and the "capsule" starts to fall.

flerchin wrote:

A barometric pressure sensor would be the way to go. Some of the smartphones with 6-axis sensor packages could also be used as a poor man's AHRS to approximate altitude better than was done here.

An iPhone altimeter app didn't work at all—it crapped out at 13,000ft. The group considered a "military" class GPS unit that would have worked, but would have cost $1500. Initially they wanted to just see how far they could with off-the-shelf mobiles and apps. Jamey said they are considering using barometric sensors or other solutions for future launches.

VoodooTrucker wrote:

Seems like the Eris could have done GPS, photos and telemetry.

So could an iPhone; so could most top smartphones, for that matter. Part of the reason they used separate devices was battery life—they were running for hours at a time. Another reason was redundancy—if one device was gathering all the data, and it failed, there were be no data. And finally, they wanted to just see what different devices could do up there.

Thats way, way cool. Love the article and thank you for the follow up post to address some questions. I too had wondered about recovery methods. I wonder if a cheap simple solution would be to tuck a parachute into the helium balloon. Once the balloon breaks the parachute would by then be "deployed". Great article none the less!

Just got off the phone with Jamey Erickson to get some answers to your questions.

flerchin wrote:

A barometric pressure sensor would be the way to go. Some of the smartphones with 6-axis sensor packages could also be used as a poor man's AHRS to approximate altitude better than was done here.

An iPhone altimeter app didn't work at all—it crapped out at 13,000ft. The group considered a "military" class GPS unit that would have worked, but would have cost $1500. Initially they wanted to just see how far they could with off-the-shelf mobiles and apps. Jamey said they are considering using barometric sensors or other solutions for future launches.

"military class GPS for $1500" = DAGR.

Unless one of these guys is in the military and has had one issued to them, i'm not sure where they would have gotten a a DAGR to use. I'm also not sure that they should be using a DAGR a) because its not theirs, its just issued to them b) i'm not sure about hooking up home-brew experemental gear to one of the J ports on a DAGR to get the telemetry.

For the record, i was just up at Pike's Peak a few weekends ago (people who come to town love to go up there) and i had zero issues with my iPhone telling me i was at 14,056 ASL with a +/- of 62 feet. So that's not a function of the GPS receiver or of the GPS crapping out at 13,000 ASL.

Here is an article where they not only explain the limitations (its either/or speed and altitude, not both), but they also note that they tracked it up around 60,000 ASL.

Just got off the phone with Jamey Erickson to get some answers to your questions.

flerchin wrote:

A barometric pressure sensor would be the way to go. Some of the smartphones with 6-axis sensor packages could also be used as a poor man's AHRS to approximate altitude better than was done here.

An iPhone altimeter app didn't work at all—it crapped out at 13,000ft. The group considered a "military" class GPS unit that would have worked, but would have cost $1500. Initially they wanted to just see how far they could with off-the-shelf mobiles and apps. Jamey said they are considering using barometric sensors or other solutions for future launches.

"military class GPS for $1500" = DAGR.

Unless one of these guys is in the military and has had one issued to them, i'm not sure where they would have gotten a a DAGR to use. I'm also not sure that they should be using a DAGR a) because its not theirs, its just issued to them b) i'm not sure about hooking up home-brew experemental gear to one of the J ports on a DAGR to get the telemetry.

For the record, i was just up at Pike's Peak a few weekends ago (people who come to town love to go up there) and i had zero issues with my iPhone telling me i was at 14,056 ASL with a +/- of 62 feet. So that's not a function of the GPS receiver or of the GPS crapping out at 13,000 ASL.

Here is an article where they not only explain the limitations (its either/or speed and altitude, not both), but they also note that they tracked it up around 60,000 ASL.

Military Class is a loose description. We were not intending to use anything that would get us in trouble, but were actually looking into this device: http://www.brickhousesecurity.com/gps-s ... cking.htmlAs it would provide us a better tracking system at higher altitudes and would not rely on cell phone towers to send back location, but was more of a 2 way GPS signal transmitter. Cost of the machine (it appears to be on SALE now) plus activation plus monthly tracing service subscription worked out at about $1,200-$1,500 bucks, which was just too expensive for our tastes.

Obviously there are limits to helium... How much would it take to launch a small payload to orbit with rockets? Obviously the cost would be much higher, but I'm still curious... or if it'd even be remotely legal

Here's an idea:Lift a rocket with the balloon, then release it at some high altitude. It drops, centered between three parachutes. Then the parachutes lines release and it ignites.

I've been putting together a project after being inspired by several groups. The footage is absolutely amazing. Trying to stabilize the pod from spinning is a hurdle at the moment. I'm surprised they picked such a nasty day (and obviously windy) day to launch. Wisconsin is pretty drafty at this time of year (grew up there).

Any reason to not add a relief valve that is altitude sensitive (a strain gauge that calibrated for the balloon stretching to a particular diameter perhaps) You could potentially keep your balloon aloft for a really long time doing that.

Obviously there are limits to helium... How much would it take to launch a small payload to orbit with rockets? Obviously the cost would be much higher, but I'm still curious... or if it'd even be remotely legal

Here's an idea:Lift a rocket with the balloon, then release it at some high altitude. It drops, centered between three parachutes. Then the parachutes lines release and it ignites.

I wonder how high you could get with a setup like that.

Amateur rocketry in the 'States is limited in the classes of engines that can be bought, and you can't put in a guidance system (otherwise it's classified as a "missile"). That's been the case since well before 9/11, if you're wondering. The kinds of propellants you can use to home-build are also regulated themselves (since they tend to be highly explosive). There are some impressive hobby rockets, but the bigger ones would be impractical to lift via weather balloon.

I was wondering if there was some FAA coordination - and then was glad to see the reference about the gold reflector

-Martin <><

There was definitely a LOT of FAA coordination. Spoke with them several times before launch to both confirm at A) We knew what we were doing and B) we were operating within the FAA Part 101 guidelines. After that, it was a simple call to our local rep within 1-3 minutes of launch so he could relay the info to local controllers.

Amateur rocketry in the 'States is limited in the classes of engines that can be bought, and you can't put in a guidance system (otherwise it's classified as a "missile"). That's been the case since well before 9/11, if you're wondering. The kinds of propellants you can use to home-build are also regulated themselves (since they tend to be highly explosive). There are some impressive hobby rockets, but the bigger ones would be impractical to lift via weather balloon.

Specifically named gasesAcetylene cylinders are maroon.Argon cylinders have a dark green shoulder.Carbon dioxide cylinders have a grey shoulder.Chlorine cylinders have a yellow shoulder.Helium cylinders have a brown shoulder.Hydrogen cylinders have a red shoulder.Nitrous oxide cylinders have a blue shoulder.Nitrogen cylinders have a black shoulder. (Previously grey, in the United Kingdom).Oxygen cylinders have a white shoulder. (Previously black, in the United Kingdom).

Is there a difference between tracking (including a gps unit) and guidance (which suggests some ability to guide and control the projectile)? My interpretation is that simply tracking the device with no control over its movements and no targeting system would not run afoul of laws defining missiles.

"The Garmin dropped altitude tracking around 30,000 feet, but based on what we know about the winds and everything it went as high as 95,000 to 105,000 feet. You don't get photos of Earth curvature until you get to about 100,000 feet," he said.

I'd be interested in more info about how they calculated the altitude. I could be mistaken, but looking at the video it seemed that the Earth curved more when the surface was at the top of the frame than in the middle, implying that it was the lens that was doing the "curving".